‘‘You got lucky on that one,’’ he told Mack as they walked back to their huddles.

Mack told Ifedi he had something else for him. One play later — after Ifedi was flagged for a false start, no less — Mack lined up opposite him, powered past him and swatted the ball out of quarterback Russell Wilson’s hand with his left arm. The Seahawks recovered the fumble, but Mack sent his message.

On Tuesday — two weeks and three days after the Bears traded for him — Mack’s dominance continued to resonate with coach Matt Nagy.

Nagy admitted his play-calling has been changed by the impact Mack has had on the Bears’ defense. With the Bears ahead by two touchdowns and positioned at the Seahawks’ 41 with 4:29 left, Nagy was content to play things conservatively, running Jordan Howard twice and then having him catch a five-yard pass to force the Seahawks to use their final timeout.

‘‘It is different,’’ Nagy said. ‘‘And he’s shown now two weeks in a row what he can do. When you’re on the other side of the ball and you’ve got a Khalil Mack that you’ve got to prep for — you saw the amount of times that they were trying to double-team him and chip him. That’s what he’s going to see.’’

The Seahawks devoted much of their pass-protection attention to Mack, using tight ends to chip away at him before he could rush Ifedi, who jab-stepped back and waited.

That allowed the Bears to use the numbers to their advantage. Mack finished with one of the Bears’ six sacks. Inside linebacker Danny Trevathan had two sacks and a forced fumble. Safety Eddie Jackson had a sack and a forced fumble. Nose tackle Eddie Goldman and outside linebacker Aaron Lynch had sacks, too.

With Mack as their centerpiece, the Bears lead the NFL with 10 sacks. Mack has two — as many as the Raiders, who traded him away.

Mack said Monday he didn’t want to answer any questions about Raiders coach Jon Gruden, who said he had no regrets about trading Mack to the Bears.

‘‘Don’t care about that,’’ he said. ‘‘I only care about what’s going on here.’’

Mack already has grown fond of defensive coordinator Vic Fangio.

‘‘He challenges you — quietly,’’ he said. ‘‘He has his own little swag about him, that Italian Mafia kind of swag to him.’’

The scary part is that Mack has dominated while still adjusting to his new life. He said he’s still adjusting in terms of learning the playbook, getting settled off the field and even learning the names of people inside Halas Hall.

Nagy said Mack’s presence allows quarterback Mitch Trubisky more freedom to learn on the job. Mistakes, such as his two interceptions during a five-play span Monday, aren’t game-killers, as evidenced by the fact the Bears forced three-and-outs after both picks.

‘‘It helps you out offensively because [Mack] raises the level of every player on defense,’’ Nagy said. ‘‘And when you have that . . . it’s infectious, and it raises the level of your offense. So once we start really getting this thing going offensively, then it will be fun.’’